OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Walk Behind Lawn Mower Frames Question On Scott Bonnar Cylinder Mowers Scott Bonnar Standard - Villiers Petrol

Hi Jack,

The engine that I have shown a photo of and the one on Woodsy's mower are both XI-C engines and from what I can see in the Scott Bonnar factory picture, this engine also appears to be the same (albeit with some minor differences).

Pre-war Villiers engines generally had a Mark (series) number identified by Roman numerals and a letter that identified the nominal engine capacity. The letters that tend to be seen in mower applications are: A (250cc), B (350cc) and C (150cc). It would appear that the letter prefix associated with the serial number (e.g. WLA) identifies particular specifications.

If we look at Scott Bonnar's use of Villiers engines at this time, there appears to be two main specifications - WL and WLA. It is not overly clear as to what the exact differences are. However, a visual comparison indicates that the key difference is the fitment of the fan and shroud. The photos below compare the two - NB both engines are Mk XI-C engines (photos by Woodsy and Stationary).




Villiers WL (No 53376)




Villiers WLA (No 53929)

Cheers,

Sir Chook